move most isikukood.js usage to utils

lib/utils.ts

@@ -91,8 +91,61 @@ export function getBmiBackgroundColor(bmiStatus: BmiCategory | null): string {
 }
 
 export function getGenderStringFromPersonalCode(personalCode: string) {
-  const person = new Isikukood(personalCode);
-  if (person.getGender() === Gender.FEMALE) return 'common:female';
-  if (person.getGender() === Gender.MALE) return 'common:male';
-  return 'common:unknown';
+  switch (PersonalCode.parsePersonalCode(personalCode).gender) {
+    case 'F':
+      return 'common:female';
+    case 'M':
+      return 'common:male';
+    default:
+      return 'common:unknown';
+  }
+}
+
+type AgeRange = '18-29' | '30-39' | '40-49' | '50-59' | '60';
+export default class PersonalCode {
+  static getPersonalCode(personalCode: string | null) {
+    if (!personalCode) {
+      return null;
+    }
+    if (personalCode.toLowerCase().startsWith('ee')) {
+      return personalCode.substring(2);
+    }
+    return personalCode;
+  }
+
+  static parsePersonalCode(personalCode: string): {
+    ageRange: AgeRange;
+    gender: 'M' | 'F';
+    dob: Date;
+    age: number;
+  } {
+    const parsed = new Isikukood(personalCode);
+    const ageRange = (() => {
+      const age = parsed.getAge();
+      if (age >= 18 && age <= 29) {
+        return '18-29';
+      }
+      if (age >= 30 && age <= 39) {
+        return '30-39';
+      }
+      if (age >= 40 && age <= 49) {
+        return '40-49';
+      }
+      if (age >= 50 && age <= 59) {
+        return '50-59';
+      }
+      if (age >= 60) {
+        return '60';
+      }
+      throw new Error('Age range not supported');
+    })();
+    const gender = parsed.getGender() === Gender.MALE ? 'M' : 'F';
+
+    return {
+      ageRange,
+      gender,
+      dob: parsed.getBirthday(),
+      age: parsed.getAge(),
+    }
+  }
 }